Top 10 Medical Mysteries We Tried to Solve in 2008

­When people say that they'll keep you in their prayers, it's usually because they're worried about you. Perhaps you've been laid off or you're dealing with a rebellious child. Or maybe you're sick.

We know that activities such as praying and meditation can lower a person's blood pressure and heart rate, which is a plus as far as your health is concerned. But can praying for someone else, also known as intercessory prayer, make a difference?

Unfortunately, it's difficult to test something that's faith-based in a scientific way. The studies that have been done have gotten mixed results: Some show a significant difference in the health of people being prayed for, while others actually demonstrate a decline.

But if we can't figure out how exactly to measure the effects of prayer or how to design a foolproof study, why do scientists keep trying? Simple: Because people believe that prayer works. According to one study, 85 percent of people pray when they're dealing with some sort of medical problem.